Kawasaki front brake problem

Before you install a new master cylinder you are supposed to bench bleed it to get all the air out first then install it the bleed the wheel cylinders the farthest from the cylinder fit so it s like this /1\RR/2\LR/3\RF/4\LF IF YOU DIDN'T BENCH BLEED IT YOU MOST LIKELY BLEW THE PRIMARY SEALS IN IT BUT YOU CAN TRY TO BENCH BLEED IT TO SEE IF IT RESPONDS AND GETS VERY STIFF WHEN YOU APPLY FORCE TO THE PISTON TO PUSH IT IN WITH A BLEEDER KIT INSTALLED ////FITTINGS FOR THE CYLINDER WITH HOSES YOU SUBMERGE INTO THE BRAKE FLUID IN THE CYLINDERS FRONT AND BACK AT THE SAME TIME HELD LIGHTLY IN A VISE TO HOLD IT STEADY

did you bleed the rear wheels or just the front
air still in the system possibly in the master cylinder

please tell me you honed the caliper before putting new piston and seals in also the inner seal is probally backwards there is only one way they go on it is to relieve the pressure off the rotor it acts like a spring if you believe you did it all correct check the porportioning valve

Try bleeding it, if that doesnt work you will need a new master cylinder/ master cylinder rebuild kit, brake seals or brake line, depending on whats leaking. The master cylinder and brake line can come off ANY bike as long as they are the right length (brake line) or fit on the handle bars (master cylinder)

leave the bleed nipples open for about five mins with the resevoir topped up,the fluid should have started coming out the bleed nipples by then,then carry on with bleeding as normal.

Hi, this means that the pistons of your front brake are not recovering properly.
If you feel confortabe with that job, you must remove brake caliper , then remove cilinders and all the protection rubber and sealing rings. Give the cilinders a good cleaning (check for scrathes or rust) replace sealers and reasemble all. Change the brake fluid and purge the circuit properly
good luck

I expect it has air in the slave cylinder. Bleeding the brakes will get rid of the air. Check if the brakes are spongy. If they aren't, make sure the spring plates behind the pads are fitted. They ensure the pads are pushed back into the calliper a little bit, reducing heat and wear.

try using a line locker close to master cyclinder ,lever should go rock hard if it has no air in system,work line locker down lines to see if lever stays hard.
also check the lever travel to make sure that lever is pushing on master cyclinder plunger as a lot of after market levers dont have correct casting and have to travel in a long way before brakes work even when system is bled. also check to make sure calliper carriers are not bent and pads not sitting square on rotors.
hope this helps

Does all the usual tricks include wrapping a thick bungee cord around the brake lever and leaving it overnight? That should force any residual air bubbles to the top of the system where the master cylinder should replace them with fluid.

If that does not work try installing some new bleed screws, even speed bleeders.

while the seals in the calipers are replaceable, its probably easier just to get a new/re manufactured caliper. if for any reason the seals don't work perfectly you could lose control of the vehicle when attempting to stop. with that said i'll try to explain the best i can how to replace the seals in the calipers for that vehicle.

1. jack up the front of the vehicle, place on jackstands and remove the front wheels, make sure the parking brake is on
2. unbolt the caliper and unbolt the brake line from the caliper and take caliper to a clean bench
3. remove the dust boot retaining ring on the caliper that holds the boot to the caliper itself
4. using a blowgun with a rubber tip apply low pressure compressed air where the brake line was bolted to the caliper to push the piston out of the bore (be carefull and ready because the piston may shoot out with some force)
5. when the piston comes out you will need to replace the dust boot and the seal so remove the boot and seal carefully so you don't scratch the piston ( the seal is actually in the caliper piston bore hole)and throw out the old seal and boot.
6. inspect all the surfaces and make sure there are no imperfections at all on the piston, the piston bore, or the caliper, if the surfaces are marred in anyway, replace the caliper, if they are good, using brake cleen and compressed air clean all parts then dry them
7. get the new seal and lubricate with DOT 3 brake fluid
8. install new seal into the caliper bore
9. apply a thin coat of DOT 3 brake fluid to the piston itself
10. install bottom half the the caliper piston into the caliper bore.
11. install new dust boot seal onto the piston
12. compress the piston to the bottom of the caliper bore
13. fully seat the dust boot seal into the caliper and install retaining ring
14. reinstall on vehicle (make sure to use a NEW copper washer on the brake line to caliper fitting) and bleed the braking system while checking for leaks.

repeat process for the other side.

if the caliper leaks at all from the piston after seal replacement, replace the caliper.

make sure you properly bleed the brakes before attempting to drive your car.

*these direction were extracted from personal experience and manufacturer information*

any other questions just ask!